Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan
Abstract:
Diastereoselective introduction of nucleophiles into l-proline derivatives at the 5-position was achieved with suitable selection of N-protecting group. N-Methoxycarbonylated or benzyloxycarbonylated l-proline derivatives reacted with arene to give cis-arylated products. On the other hand, N-benzoylated l-proline derivative preferentially gave trans-arylated product, which could be easily transformed into optically active C2-symmetrical pyrrolidine derivative. Such derivative 5 worked well as an organic activator in the asymmetric reduction of aromatic imines by Cl3SiH.